The Moonlit Tower
A beautifully-written game based on Asian mythology. To explain the premise would be difficult, but that's not really an issue -- the best thing about this game is simply enjoying the setting, which is full of rare and lovely imagery. The puzzles are occasionally a bit elusive, but the built-in hint system helps somewhat with that problem. There are also multiple endings and an extensive set of notes describing the game's background -- quite a lot of polish for a (relatively) brief piece.